Declarative attestation authoring

[teranos]

Summary

• Add qntx { node { url } } and attestation { subject, predicate, context, attributes } blocks to pbt
• CTFE parser, sizing pass, and static assert tests for both blocks
• ground attest subcommand: POSTs all declared attestations to all QNTX nodes (0.4s timeout, fire-and-forget)
• make install runs ground attest automatically after binary install
• Fix project-scoped deferred delivery: gate on main/master when in a git repo, deliver unconditionally otherwise

Test plan

• CTFE static assert tests pass for qntx/attestation parsing
• make install posts to running nodes (201), skips unreachable nodes fast
• Batch raven:routes attestation accepted by QNTX